Methods and systems for improving airway patency

ABSTRACT

An oral device for improving airway patency includes a tongue constraint and a negative pressure source. The tongue constraint engages the patient&#39;s tongue to maintain a clear region below the palate in an oral cavity and allow an anterior portion of the tongue to rise. By applying a negative pressure in the clear region, an airway behind the soft palate or tongue of the patient can be maintained. The tongue constraint is usually connected to an anchor. The anchor may be held between the patient&#39;s teeth or may engage the inferior surface of the palate. Another oral device for improving airway patency includes a lateral tongue structure and a negative pressure source.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 13/912,021, filed Jun. 6, 2013, which is a continuation of U.S.patent application Ser. No. 12/882,054, filed on Sep. 14, 2010, now U.S.Pat. No. 8,505,540, which is a continuation-in-part of U.S. patentapplication Ser. No. 12/269,683, filed on Nov. 12, 2008, now U.S. Pat.No. 8,122,889, which claims the benefit of U.S. Provisional ApplicationNo. 60/987,707, filed Nov. 13, 2007, the full disclosures of which areincorporated herein by reference; U.S. patent application Ser. No.12/882,054, filed on Sep. 14, 2010, is also a continuation-in-part ofU.S. patent application Ser. No. 12/840,076, filed on Jul. 20, 2010, thefull disclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to medical devices and methods.In particular, the present invention relates to an oral device that maybe held in the mouth of a patient to reduce the incidence of obstructivesleep apnea or snoring.

Obstructive sleep apnea (OSA) is a serious medical condition resultingfrom a temporary airway blockage which occurs as a patient sleeps. Theairway blockage usually occurs between the soft palate and/or the backof the tongue and the pharynx. As the patient breathes, the reduced areain the upper airway can cause snoring, and more seriously, OSA.

Sleep disruption caused by OSA can result in severe daytime sleepiness,chronic fatigue, headaches, depression, accidents, injuries, and ofparticular concern, OSA can reduce the amount of oxygen entering thelungs causing hypoxia. Hypoxia, in turn, can lead to pulmonaryhypertension, heart disease, and stroke.

Numerous invasive and less invasive treatments have been proposed forOSA. Of particular interest to the present invention, “continuouspositive airway pressure” (CPAP) delivers a continuous stream ofpressurized air directly to the person's upper airway. The positivepressure maintains patency of the airway and inhibits the collapseassociated with OSA. Although generally effective, CPAP suffers from anumber of drawbacks that have led to a high level of non-compliance. Thepatient must wear a bulky facial mask which can be uncomfortable, andthe system generates noise that can make falling asleep difficult. CPAPis also difficult to use because the mask requires careful fitting toavoid air leaks and facial discomfort and because the mask can easily bedislodged during sleep. Moreover, a number of unpleasant side effects,such as sore throats, dry throat and eyes, headaches, and skin rashesfrom the mask frequently occur. These problems have resulted in a highlevel of non-compliance with CPAP therapy.

As an improvement over CPAP, it has been proposed to apply a negativepressure to the forward end of the patient's mouth, typically at or justbehind the lips, to pull the tongue forward in order to lift the rearportion of the tongue away from the back of the airway. See, forexample, U.S. Patent Publication Nos. 2007/0277818, 2005/0166928 and2005/0166929. While promising in theory, in practice it is verydifficult to apply a vacuum in the region of the tip of the tongue toraise the base of the tongue and clear the patient's airway,particularly when the patient is lying on his or her back and gravity ispulling the tongue posteriorly. The tongue is a relatively large andcompliant organ with significant mass, and applying a vacuum over arelatively small surface area at the tip will often not be effective inraising the back of the tongue against gravity. The moist and complianttissues in the mouth are somewhat self-sealing, and this effect tends toinhibit the propagation of negative pressure, thereby confining thenegative pressures to a relatively small area near the point ofapplication. Thus, simply applying a vacuum at a location near theanterior tip of the tongue tends to draw the tongue up against the hardpalate posterior to this location, creating a seal that restricts thepropagation of vacuum through this region of contact toward the back ofthe oral cavity, where direct vacuum is usually required for maximumeffectiveness.

As another improvement over CPAP, it has been proposed to place variousdevices in direct contact with the posterior tissues of the mouth suchas the soft palate and posterior portions of the tongue. A majordisadvantage of these approaches is that contact with certain tissuesnear the posterior area of the tongue may elicit the gag reflex and inany case the presence of such devices so far back in the mouth can beuncomfortable.

For these reasons, it would be desirable to provide alternative andimproved methods and apparatus for treating obstructive sleep apnea andsnoring. The methods and devices should be non-invasive and require nosurgery or permanently implanted components. In addition, the methodsand devices should be minimally intrusive with components that arecomfortable and quiet so that disruption of the patient's sleep isminimized. Moreover, the methods and devices should avoid contacting theportions of the oral cavity that trigger the gag reflex. The methods andsystems should also be simple to implement and be effective tosignificantly improve patency of a patient's airway during sleep. Atleast some of these objectives will be met by the inventions describedhereinafter.

2. Description of the Background Art

Oral and external devices for treating sleep apnea and snoring aredescribed in U.S. Patent Publication Nos. US2005/166929; US2005/166928;US2008/0188947; US2007/0277818; US2008/0216843; and US2008/0210244; andin U.S. Pat. Nos. 7,182,082; 7,073,506; 7,073,505; 6,955,172; 6,877,513;6,494,209; 5,957,133; 5,465,734; 4,676,240; 4,304,227; 4,169,473; and3,132,647; and in Cartwright and Samelson “The effects of a non-surgicaltreatment for obstructive sleep apnea: the tongue retaining device;”Journal of the American Medical Association 248 (1982).

BRIEF SUMMARY OF THE INVENTION

The present invention provides methods and devices for improving airwaypatency in patients by drawing an anterior region of the tongue upwardly(in a superior direction toward the top of the head) whilesimultaneously drawing the soft palate against a posterior region of thetongue. The methods typically comprise selecting a patient diagnosedwith sleep apnea, where adequate diagnostic procedures are welldescribed in the medical literature. A member is engaged across anengagement region of the patient's tongue usually located between thepatient's molars sometimes referred to herein as medial region, suchthat the member divides the tongue into an anterior portion or segmentand a posterior portion or segment. A vacuum is applied to a regionbetween the tongue and hard palate to cause the anterior region of thetongue to rise in a superior direction. The soft palate is drawn againsta region of the tongue posterior to the member. In this way, the softpalate is stabilized and sleep apnea is reduced or eliminated.

Drawing the soft palate against a region of the tongue posterior to thetongue-engaging member will seal the soft palate against the tongue toisolate the oral cavity from the patient's airway, clearing the airwayfor nasal breathing while stabilizing the soft palate to inhibit sleepapnea. Usually, the entire region of the tongue anterior to thetongue-engaging member will be caused to rise, and the applied vacuumwill act on a superior portion of the soft palate. The vacuum may beapplied through one or more vacuum ports disposed on an upper orsuperior surface of the tongue-engaging member, and the tongue-engagingmember usually creates a clear region between a superior surface of themember and an inferior surface of the hard palate, where the clearregion is preferably free of structure and usually reaches to the softpalate so that the vacuum may draw the soft palate as discussed above.Further, specific embodiments, engaging the tongue-engaging member,comprises inserting a bite structure between the patient's jaws, wherethe bite structure carries the engagement member. More typically, theengagement member extends across the oral cavity between left and rightmolars. The methods thus described may further comprise sealing thepatient's lips to inhibit air from entering the oral cavity through themouth.

The member which is engaged against the engagement region of the tonguecan take a variety of configurations. Usually, the member will have anarcuate profile across the medial region of the tongue. For example, themember can be an arcuate plate extending from one side of the tongue tothe other and having a depth in the anterior posterior direction in therange from 2 mm to 25 mm, usually from 4 mm to 10 mm. The plate,however, need not have an arcuate profile and can, in other cases, havea substantially flat profile across the medial region of the tongue,typically being a flat plate having depth within the dimensions setforth above. In addition to such arcuate and flat plates, the member canfurther comprise a hard palate engagement plate which is suspended abovethe tongue-engagement plate in order to engage the hard palate and helphold the tongue-engagement plate in position. In still otherembodiments, the tongue-engaging member may comprise a dome-shapedtongue constraint which is placed over the tongue. The member can thenbe defined by a posterior edge of the dome-shaped tongue constraintwhich engages the engagement region of the tongue while the posteriorregion of the tongue may rise in a cavity or chamber formed beneath theanterior portion of the dome-shaped tongue constraint. While thesetongue-engaging members are exemplary, other geometries could beutilized so long as they result in a rise in a portion of the tongueanterior to the tongue-engagement member and closure of the soft palateagainst a posterior region of the tongue when a vacuum is applied.

The present invention still further provides oral devices useful forperforming the methods just described. An oral device according to thepresent invention will be intended for temporary placement in apatient's oral cavity and will comprise a base, a tongue-engaging memberand a vacuum conduit. The base is adapted to be held between thepatient's upper and lower teeth, and the tongue-engaging member iscoupled to the base to be held in a predetermined position relative tothe tongue. In particular, the tongue-engaging member will include aposterior structure that engages an engagement region of the tongue andan anterior structure that allows a tongue region anterior to the memberto rise relative to the medial region when the base is held between theteeth. The oral device will further include a vacuum conduit coupled tothe base and/or to the tongue-engaging member. The vacuum conduit willbe configured to apply a vacuum to a region of the oral cavity posteriorto the member (i.e., posterior to the engagement region of the tongue)to draw the soft palate down onto the posterior tongue.

The vacuum conduit and the oral devices of the present invention willtypically be configured to draw the soft palate down onto a posteriorregion of the tongue. Vacuum conduits may be configured to seal the softpalate against the tongue to isolate the oral cavity from the patient'sairway. The tongue-engaging members typically extend between thepatient's left and right molars when the base is held between the upperand lower teeth. More typically, the base will include left and rightbite structures, and the tongue-engaging member will be disposed betweensaid left and right bite structures. In specific embodiments of the oraldevices of the present invention, the tongue-engaging member will bespaced inferiorly of the hard palate when the base is held between thepatient's teeth. Such positioning of the tongue-engaging member providesa clear region free from structure between the tongue-engaging memberand the hard palate, where the clear region will extend all the way tothe patient's soft palate. This clear region allowed the vacuum to drawthe soft palate forward against the tongue as described previously. Inother specific embodiments of the present invention, the vacuum conduitmay be fluidly coupled to at least one vacuum port on a superior orupper surface of the tongue-engaging member. The oral device will oftenfurther comprise a lip seal coupled to the base and/or the vacuumconduit to inhibit air from entering the oral cavity through the mouth.

The anterior structure of the tongue-engaging member may have a varietyof configurations. In many instances, the structure will comprise anopen cavity or aperture which allows the tongue to rise therethroughwithout constraint. In other instances, the tongue-engaging member willcomprise a dome-shaped device wherein the cavity of the dome is withinthe anterior structure of the member. Other tongue-engaging members weredescribed previously with respect to the methods of the presentinvention.

Allowing and urging the anterior portion of the tongue to risesuperiorly contributes to the ability of the device to keep the airwayopen. The tongue of sleep apnea patients often falls back into theairway during sleep further blocking the airway. By causing anteriorportions of the tongue to rise, posterior portions of the tongue willmove away from the airway to inhibit blockage of the airway. An openportion or cavity in the front of the device allows the anterior mass ofthe tongue to move forward and upward into a front portion of the mouth.The bite structure of the device further advances the tongue by holdingthe jaw open slightly create more volume in the oral cavity allowingfurther displacement of the tongue into the anterior region of the mouthand away from the airway. In addition to pulling the soft palateanteriorly out of the airway, the vacuum applied between thetongue-engaging member and hard palate urges the tongue into this openanterior space and away from the airway. A fully open anterior portionof the device allows the tongue to rise up and contact the hard palateso that is can maximally fill the anterior oral cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the relevant anatomy of the nasal and oral cavities.

FIG. 2A illustrates a first embodiment of an oral device constructed inaccordance with the principles of the present invention.

FIG. 2B illustrates use of the device of FIG. 2A for inhibition of OSAwhen placed in an oral cavity of a patient.

FIGS. 3A-3C illustrate a second embodiment of an oral device constructedin accordance with the principles of the present invention, where FIG.3A is a perspective view, FIG. 3B is a top view, and FIG. 3C is a bottomview.

FIG. 4 is a perspective view of a third embodiment of an oral deviceconstructed in accordance with the principles of the present invention.

FIG. 5 is a top view of a fourth embodiment of an oral deviceconstructed in accordance with the principles of the present invention.

FIGS. 6A-6C illustrate a fifth embodiment of an oral device constructedin accordance with the principles of the present invention, where FIG.6A is a perspective view, FIG. 6B is a side view, and FIG. 6C is across-sectional view taken along line 6C-6C of FIG. 6B.

FIGS. 6D and 6E illustrate use of the device of FIGS. 6A-6C forinhibiting OSA when placed in an oral cavity of a patient, where FIG. 6Dis a side cross-sectional view and FIG. 6E is a sectional view takenalong line 6E-6E in FIG. 6D.

FIGS. 7A-7D illustrate a further embodiment of an oral deviceconstructed in accordance with the principles of the present invention,where FIG. 7A is a perspective view, FIG. 7B is a detailed view of anadjustable tongue constraint, FIG. 7C is a side view of the device, andFIG. 7D is a cross-sectional view taken along lines 7D-7D of FIGS. 8Aand 7C.

FIGS. 8A-8C illustrate yet another embodiment of an oral deviceconstructed in accordance with the principles of the present invention,with FIG. 8A being an perspective view, FIG. 8B being a side view, andFIG. 8C being a cross-sectional view taken along line 8C-8C of FIG. 8B.

FIGS. 9A-9C illustrate still another embodiment of an oral deviceconstructed in accordance with the principles of the present invention,where FIG. 9A is a perspective view, FIG. 9B is a top view, and FIG. 9Cis a cross-sectional view taken along line 9C-9C of FIG. 9B.

FIG. 9D illustrates use of the device of FIGS. 9A-9C for inhibiting OSAwhen placed in an oral cavity of a patient.

FIG. 10 is a perspective view illustrating a patient asleep at nightusing the apparatus of the present invention.

FIG. 11 is a schematic illustration of a control system or console foruse in aspirating a negative pressure in the oral devices of the presentinvention.

FIGS. 12A-12D are top, oblique, front and side cross-sectional views,respectively of an oral device according to the invention in a furtherembodiment thereof.

FIG. 12E is a side cross-sectional view of the oral device of FIGS.12A-D positioned in a patient's oral cavity.

FIGS. 13A-13E are top, front oblique, rear oblique, front, and sidecross-sectional views, respectively, of an oral device according to theinvention still another embodiment thereof, in which the lip seal isremoved for clarity.

FIGS. 14A-14C are top, front and side cross-sectional views,respectively of an oral device according to the invention in stillanother embodiment thereof, in which the lip seal is removed forclarity.

FIGS. 15A-15D are top cutaway, oblique, front, and side cross-sectionalviews, respectively of an oral device according to the invention instill another embodiment thereof, in which the lip seal is removed forclarity.

FIGS. 16A-16C are oblique, front, and side cross-sectional views,respectively of an oral device according to the invention in stillanother embodiment thereof, in which the lip seal is removed forclarity.

FIGS. 17A-17D are top cutaway, oblique, front and side cross-sectionalviews, respectively of an oral device according to the invention instill another embodiment thereof, in which the lip seal is removed forclarity.

FIG. 17E is a schematic illustration of a system for applying differentpressures to different regions of the oral cavity shown with the oraldevice of FIGS. 17A-D.

FIGS. 18A-18C are top, oblique and side cross-sectional views,respectively of an oral device according to the invention in stillanother embodiment thereof, in which the lip seal is removed forclarity.

FIGS. 19A-19B are oblique and side cross-sectional views, respectivelyof an oral device according to the invention in still another embodimentthereof, in which the lip seal is removed for clarity.

FIGS. 20 and 20B are top and side cross-sectional views, respectively ofan oral device according to the invention in still another embodimentthereof, in which the lip seal is removed for clarity.

FIG. 20A is a side partial cross-section taken along line A-A in FIG.20.

FIGS. 21A-21B are oblique and side cross-sectional views, respectivelyof an oral device according to the invention in still another embodimentthereof, in which the lip seal is removed for clarity.

FIG. 21C is a schematic illustration of a system for deliveringdifferent pressures to different regions of the oral cavity, shown withthe oral device of FIGS. 23A-B.

FIGS. 22A-22C are oblique, top, and side cross-sectional views,respectively of an oral device according to the invention in stillanother embodiment thereof.

FIGS. 23A and 23B illustrate a further embodiment of an oral deviceconstructed in accordance with the principles of the present invention,with FIG. 23A shown in full line perspective view and FIG. 23B shownwith portions broken away.

FIG. 24 is a side view of the oral device of FIGS. 23A and 23B.

FIG. 25 is a side view of a second embodiment of a further oral devicewhich is a variation of the device FIGS. 23A, 23B and 24.

FIG. 26 is a perspective view of yet another embodiment of an oraldevice constructed in accordance with the principles of the presentinvention.

FIG. 27 is a perspective view of still another oral device constructedin accordance with the principles of the present invention.

FIGS. 28 and 29 are schematic illustrations of the placement of the oraldevice of FIG. 25 in an oral cavity with the soft palate engaging aposterior surface of the device in FIG. 28 and the soft palatespaced-apart from the oral device in FIG. 29, but in both cases thissoft palate engages a posterior portion of the tongue.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the anatomy of the oral and nasal cavities relevantto obstructive sleep apnea (OSA) and the placement of the devices of thepresent invention will be described. The upper teeth UT of the patientare anchored in the hard palate HP, and the lower teeth LT are anchoredin the lower jaw or mandible LJ. The soft palate SP extends in arearward or posterior and inferior direction from the hard palate, andtogether the hard palate and soft palate divide the nasal airway NA fromthe oral cavity OC. The lower extent of the oral cavity is largelydefined by the upper surface of the tongue T in this view, and it willbe appreciated that both the soft palate SP and the tongue are mobilestructures capable of movement between the positions shown in full lineand broken line in FIG. 1. A nasal airway NA extends inferiorly into thepharynx P which defines the airway generally behind the soft palate SPand the tongue T. The regions on the tongue and soft palate shown with aheavy dashed line are the areas responsible for the gag reflex GR.

Obstructive sleep apnea occurs when either the soft palate, the tongueor both move in a posterior direction so that they contact the rear orposterior surface of the pharynx P. The posterior motion of the softpalate and/or tongue may also reduce the size of the airway withoutcontacting the pharynx P causing a partial blockage. The temporaryblockage of the airway behind the soft palate and tongue will cause thedisrupted breathing pattern characteristic of OSA and usually associatedwith snoring.

Referring now to FIGS. 2A and 2B, a first exemplary oral device 10constructed in accordance with the principles of the present inventioncomprises an anchor structure 12, a tongue constraint 14, and a plenumstructure 16 adapted to aspirate the oral cavity and apply a negativepressure therein while the anchor structure is held in the patient'smouth. The anchor structure 12 includes a bite structure 20 having upperand lower tooth-receiving channels 22 and 24, respectively, as best seenin FIG. 2B. The portions of upper and lower tooth-receiving channels 22and 24 that contact the lips help to create a seal which inhibits entryof air into the oral cavity. The tongue constraint 14 comprises aJ-shaped tube 26 which passes through or is otherwise coupled to theanchor structure 20 so that a posterior end 28 of the tube lies over aposterior end of the medial region of the tongue, as best seen in FIG.2B. Optionally, the tongue constraint 14 may further include a tongueretraction plate 30 which extends over the medial region of the tongueto help constrain the tongue inferiorly to create a clear or open region32 over the tongue and beneath the soft palate, as best seen in FIG. 2B.

The plenum structure 16 is partly formed within the J-shaped tube 26 ofthe tongue constraint and partly provided by a separate lateral tonguevacuum tube 34. The vacuum tube 34 has a Y-shaped geometry with legs 36and 38 extending laterally and generally inferiorly on either side ofthe tongue. Legs 36 and 38 serve to create negative pressure in portionsof the oral cavity that may otherwise be sealed off by the compliantmouth tissues, thereby helping to urge the tongue and soft palateforward. Both the J-shaped tube 26 and the tongue vacuum tube 34 have aplurality of vacuum ports 40 and 42, respectively, distributed alongtheir lengths. Typically, the tubes 26 and 34 will have inside lumendiameters in the range from 0.5 mm to 5 mm, with ports having widths inthe range from 0.5 mm to 10 mm, often having an oval shape asillustrated, but optionally having other shapes. By having multiplepoints spaced throughout the oral cavity, particularly within theposterior region of the oral cavity, the ability to provide a continuousaspiration to maintain the desired level of negative pressure or vacuumis greatly enhanced. It will be appreciated that even if certain ones ofthe vacuum ports 40 and 42 become blocked, others will remain open toexpose the clear region created by the tongue retraction plate 30 to thedesired pressure. As can be seen in FIG. 2B, vacuum tube 26, plenumstructure 16, and clear region 32 provide a continuous vacuum flow pathfrom the patient's lips to the soft palate through which vacuum may beapplied. By applying the desired vacuum or negative pressure, the softpalate SP will be drawn inferiorly and anteriorly against the posteriorregion of the tongue T, generally forming a seal which substantiallyfluidly isolates the airway from the vacuum flow path and permits thenegative pressure to draw the soft palate and tongue anteriorly to openup the airway behind the soft palate and tongue adjacent the pharynx P.

Referring now to FIGS. 3A-3C, a second exemplary embodiment of the oraldevice 50 will be described. The oral device 50 includes generally thesame components as the oral device 10 with an anchor structure 52 beinggenerally identical to the anchor structure 12. A tongue constraint 54is similar to tongue constraint 14, except that it is formed from a tube56 having an oval tubular structure 58 at its proximal end. The ovaltube 58 allows the vacuum or negative pressure connection to extendthrough both sides of the tube, rather than terminating at one end, aswith the J-shaped tube 26 of device 10. This provides for more robustoperation by allowing negative pressure to be applied even if the lumenof oval tube 58 becomes clogged. Oral device 50 also includes a plenumstructure comprising a tube 62 with inferiorly oriented arms 64 and 66which is generally similar to the lateral vacuum tube structure 34 oforal device 10. The arms 64 and 66, however, are curved rather thanstraight as in the earlier embodiment. Oral device 50 generally providesfor more open space 67 on the anterior side of the tongue refractionplate 68.

FIG. 4 is a further variation of an oral device 70 which is almostidentical to device 50, except that a tongue constraint structure 72 hasan arcuate or curved lateral cross section in contrast to the straightcross section of tongue constraints 54 and 14 in oral devices 50 and 10,respectively. The arcuate shape of the tongue constraint structure 72may improve the comfort of the device by allowing for a more naturaltongue position. The palate and the tongue naturally take on a similardomed shape.

FIG. 5 is a further variation of an oral device 74 which is almostidentical to device 50 with tube 76 being generally identical to tube 56and tube 78 generally being identical to tube 62. Oral device 74 alsoincludes tubes 80 and 82 which generally follow the paths of tubes 76and 78, respectively. Tube 82 bifurcates into arms 84 and 86 in asimilar manner as arms 64 and 66. Ports 88 and 90 are in fluidcommunication with tubes 82 and 80, respectively. Tubes 80 and 82 can bethereby be used to monitor the negative pressure in the oral cavity atthe locations of ports 88 and 90 by connecting tubes 80 and 82 topressure sensors. In addition fluids such as humid air or warmed salinemay be introduced via tubes 80 and 82 and ports 88 and 90 in order toenhance patient comfort by moistening the oral cavity or by helping toaspirate fluids such as saliva that may have collected in the oralcavity.

Referring now to FIGS. 6A-6E, a third exemplary embodiment of the oraldevice 92 will be described. The oral device 92 generally providessimilar components as the oral device 70. An anchor structure 96includes bite structure 98 which is configured to be held between thepatient's upper and lower teeth. Bite structure 98 does not includetooth-receiving channels and is open at the front allowing the frontteeth to overlap, thus improving patient comfort by minimizing the bulkof the device and allowing the mouth to close more than oral device 70allows. Instead of relying on tubes to convey the negative pressure,tongue constraint structure 94 is hollow and includes one or more vacuumports 99, thereby reducing the overall size and bulk of the tongueconstraint structure. Portions of bite structure 98 may be hollow andused to convey the negative pressure. A tubular structure 100 mayadditionally be employed to convey the negative pressure. A lip sealstructure 102 facilitates creating a seal at the mouth by contacting theinner surface of the lips proximate the mouth opening. The lip sealstructure 102 may also be hollow in order to convey negative pressure tovacuum ports 104 which are positioned to help ensure that negativepressure is well-distributed proximate the lips, thus providing forimproved lip sealing forces. One or more lateral tongue structures 108may be flexible and also hollow in order to convey negative pressure tovacuum ports 110 which are positioned to enhance the distribution ofnegative pressure into the oral spaces lateral to the tongue. A vacuumplenum 105 may thusly comprise contiguous hollow portions of lip sealstructure 102, tubular structure 100, bite structure 98, tongueconstraint structure 94, lateral tongue structures 108, and a vacuumtube 109 that is connected to a source of negative pressure. Optionally,lip seal protrusion 106 may enhance the formation of a seal at the lipsby concentrating lip contact forces at the protrusion. Optionally, asensor 112 such as a pressure sensor with connecting cable 114 may bemounted on tongue constraint structure 94 or on any other part of thedevice for example to monitor the pressures developed in the oralcavity.

Referring now to FIGS. 7A-7D, an oral device 146 which is very similarto oral device 92 except that it employs an adjustable tongue constraintstructure 148 which can be used with any of the oral devices describedis illustrated. Adjustable tongue constraint structure 148 has threepairs of through holes 150 at each side. Each pair of through holes 150may be engaged with a pair of the four protrusions 152 which extend fromeach of the bite structures 154. It can be appreciated that adjustabletongue constraint structure 148 may be moved superiorly, inferiorly,anteriorly, and posteriorly by engaging various pairs of holes 150 withappropriate pairs of protrusions 152 as best shown in FIG. 7A. Suchadjustability facilitates the fitting of oral device 146 to the anatomyof a particular patient. Adjustable tongue constraint structure 148 ishollow and is connected to vacuum tube 154 by means of flexible tube 156and tubular structure 158. Bite structures 154 may also be hollow inorder to convey negative pressure as with oral device 92.

Referring now to FIGS. 8A-8C, an oral device 160 which is very similarto oral device 92 except that it employs a flexing tongue constraintstructure 162 which can be used with any of the oral devices describedis illustrated. Flexing tongue constraint structure 162 is very similarto tongue constraint structure 94 except that a window 164 is formed ateach lateral end of the flexing tongue constraint structure 162. Windows164 are sized to create a pair of narrow flexure arms 166 at eachlateral end of flexing tongue constraint structure 162. Flexure arms 166are fabricated from a flexible material such as polyurethane so thatflexing tongue constraint structure 162 is allowed to flex anteriorlywhen the portion of the tongue it contacts is urged anteriorly by thenegative pressure in the oral cavity. This anterior motion of flexingtongue constraint structure 162, best seen in FIG. 9B, may facilitatefurther anterior motion of the tongue and soft palate as compared withoral device 92, thereby improving the ability of oral device 160 to openthe airway. Because flexing tongue constraint structure 162 and flexurearms 166 are hollow, negative pressures are conveyed in a very similarmanner as with oral device 92.

Referring now to FIGS. 9A-9D, an oral device 170 having an alternativeanchor structure 172 will be described. In all previous embodiments, theanchor structure of the oral device has been intended to be held betweenthe patient's teeth in order to provide a support for the tongueconstraint. That is, the anchor structure held between the patient'steeth is attached to the tongue constraint and transmits force tomaintain the tongue position through the anchor between the teeth. Inthe oral device 170, the anchor structure 172 has an upper surface 174which is configured to rest against the inferior surface of the palate,as best seen in FIG. 9D. A pair of depending sidewalls 176 and 178adjoin to a curved or arcuate tongue constraint 180 which includes anopen interior or plenum 182 having a plurality of ports 184 over itsupper surface.

Vacuum or negative pressure can be provided to the plenum 182 by aU-shaped tube 186 which is adapted to circumscribe the patient's teethTE, as best shown in FIG. 9B. It can be seen that the teeth can be fullyclosed with the tube extending around the rear molars when the anchorstructure 172 is positioned in the oral cavity, as shown in FIG. 9D. Aflexible tube 188 is connected to the vacuum supply tube 186 through alip seal structure 190, as shown in cross section in FIG. 9C. The lipseal structure 190 has a flat and tapered shape so the patient's upperand lower lips can conform to it thereby facilitating the seal in theoral cavity as a vacuum or negative pressure is drawn through thedevice.

Referring now to FIG. 10, in addition to the portable battery poweredvacuum source described earlier, the oral devices of the presentinvention may receive the desired vacuum or negative pressure from atabletop unit 200 which can be operated off of house current and/orbattery power. The tabletop unit 200 may be connected to the oral device(within the patient's mouth in FIG. 10) through a relatively long,flexible, crush-resistant, small and lightweight connector tube 202. Thelong connector tube is convenient and allows the patient to sleepcomfortably in any position with minimal disruption.

The tabletop control unit 200 may comprise a number of internalcomponents, as best illustrated in FIG. 11. The tabletop control unitwill usually include a user interface 204. In order to generate thenegative pressure used by the oral devices described above and to reducethe accumulation of fluid within the mouth, one or more pumps 220,sensors 222 for flow, pressure, or the like and traps 224 will usuallybe provided. The traps 224 remove saliva and other substances from thetubing to prevent them from entering the pumps 220. The sensors 222 maybe used to determine if the device is operating and being appliedproperly. For example an air leak would generate higher than normal flowand the user could be alerted that there is a problem. Optionally valve232 may be provided for briefly allowing air to enter the device or oralcavity in order to facilitate aspiration of fluids that have collectedin the oral cavity or device. Optionally fluid source 214 and pump 206for providing moisture and a heater/cooler 216 for heating or coolingthe fluid, may be provided. Electronics and power control module 208will provide for the desired control functions of the unit. Optionally afeedback loop may be configured to monitor the pressure in the oralcavity for example as described above using tubes 80 and 82 connected toa pressure sensor 212 and to adjust the power of the one or more vacuumpumps 220 in order to maintain the desired level of negative pressure inthe oral cavity. Varying distributions of saliva in the tubing thatconnects the control unit 200 to the oral devices described above willcreate a pressure differential and such a feedback loop couldcontinually compensate for this varying differential. Optionally, a port210 may be provided for external connection of the control unit to acomputer or data distribution network. Each of these components may beconnected to the oral device through appropriate tubes, wires or otherconnectors 230.

A further embodiment of an oral device according to the invention isillustrated in FIGS. 12A-D. Oral device 280 has a tongue constraint 282with a bite structure 284 integrally formed with or fixed to the tongueconstraint 282 around its anterior and lateral edges. Similar toprevious embodiments, bite structure 284 has a U-shaped channel 286adapted to receive the upper teeth so as to anchor the oral device 280in the oral cavity. U-shaped channel has an outer wall 287 which extendssuperiorly to cover at least a portion of the upper teeth, and an innerwall 289 which may be shorter or optionally eliminated entirely. Outerwall 287 and/or inner way 289 may have a height to cover the upper teethentirely so as to inhibit leaks from the oral cavity posterior to theteeth.

Tongue constraint 282 comprises a curved or dome-shaped plate 288 havinga concave inferior surface adapted to engage the superior surface of thetongue to constrain at least a portion of the tongue in a positionspaced apart from the patient's hard palate, thereby creating a clearregion superior to plate 288 and inferior to the hard palate thatcontinuously extends from the posterior side of bite structure 284 tothe soft palate. In preferred embodiments, the superior surface oftongue constraint 282 is spaced apart from the patient's hard palate byat least about 0.5 mm. Tongue constraint 282 preferably has sufficientrigidity to constrain the tongue in a position-spaced apart from thehard palate. While some flexibility is possible, tongue constraint 282will have sufficient resilience and strength to overcome any deflectioncaused by movement of the tongue to return to an unbiased position inwhich the tongue is spaced apart from the hard palate. In order to applya distributed force across a broad area of the tongue, tongue constraint282 is preferably configured to engage at least ½ of the width of thetongue (in the lateral direction, left to right). In this embodiment,plate 288 of tongue constraint 282 spans the entire distance across theopen end of U-shaped bite structure 284 between the patient's left andright molars and is thus configured to engage substantially the entirewidth of the tongue.

As in previous embodiments, the plate 288 preferably engages the medialregion of the tongue so as not to contact the region of the tongue thattends to initiate the gag reflex. Plate 288 is preferably continuousthroughout the area circumscribed by bite structure 284 (except forvacuum ports 296, described below). Plate 288 will usually engage themedial surface of the tongue at a location that is at least about ⅓ ofthe way, more preferably at least about ½ of the way, from the anteriortip of the tongue to the posterior end of the tongue. Usually, plate 288engages the medial surface at a point posterior to the midpoint betweenthe anterior and posterior ends of the hard palate. Plate 288 may engagethe tongue as far back as or even beyond the posterior end of the hardpalate where it joins to the soft palate; however, plate 288 isconfigured to allow the soft palate to engage the posterior side ofplate 288 in a position in which the airway is at least partially open,so will usually not extend posteriorly more than about 20 mm beyond theposterior end of the hard palate HP, and preferably not more than about25 mm posteriorly beyond the normal location of the patient's secondmolars. If an imaginary cylinder were drawn between the patient'snasopharynx and laryngopharynx with diameter about the same as thelaryngopharynx, in preferred embodiments plate 288 would not intersectsuch a cylinder.

Plate 288 forms a soft palate landing pad 290 on its posterior sidehaving a posterior surface 292 which angles inferiorly and posteriorlyfrom the apex A of the dome-shaped plate 288. Soft palate landing pad290 is adapted to engage the soft palate when vacuum is applied throughthe oral device. Posterior surface 292 may be arcuate, spherical, planaror a combination thereof. In exemplary embodiments, as shown in FIG.12D, posterior surface 292 extends a length L of at least about 5 mmfrom the inferior surface 295 of bite structure 284, and posteriorsurface 292, or a plane P tangential with posterior surface 292, isdisposed at an angle a of at least about 45°, more preferably about60-135°, and most preferably about 90-135°, relative to a horizontalplane H containing an inferior surface 295 of the bite structure 284.Horizontal plane H is generally coplanar with the occlusal plane, theplane in which the upper and lower teeth meet when the patient bitestogether.

Plate 288 has a plurality of vacuum ports 296 extending entirely throughits thickness. Vacuum ports 296 are disposed in locations on plate 288selected to direct negative pressure (suction) within the clear regionsuperior to plate 288 against the superior surface of the tongue on theinferior side of plate 288. Various locations and arrangements arepossible, but in one embodiment vacuum ports 296 are disposed within acentral region of plate 288 which contacts the medial region of thetongue. In this embodiment vacuum ports 296 are arranged in a gridgenerally centered on apex A in a central portion of plate 288 andextending laterally in both directions to points adjacent to U-shapedchannel 286, with soft palate landing pad being free of vacuum ports.Optionally, vacuum ports 296 may also be provided on soft palate landingpad 290.

As an alternative to vacuum ports 296 shown, plate 288 may be made of aporous material to allow air to pass through it, such as a porouspolyethylene or other porous polymer. As a further alternative, plate288 may have very small or even microscopic holes created by laserdrilling, etching, or other suitable process throughout its entire areaor in a selected region or regions thereof.

A vacuum tube 298 is fixed to the surface of plate 288 and extendsanteriorly through plate 288 and bite structure 284 where it connects toan extension tube 300, which is connectable to a suction source such asa vacuum pump or portable vacuum source as described in earlierembodiments. Optionally, a detachable connector (not shown) may beconnected to the end of extension tube 300 to allow detachableconnection to a complementary connector (not shown) on a portable vacuumsource or a tube extending to the vacuum source. Vacuum tube 298preferably has a plurality of holes 302 on a sidewall thereof, and mayhave an open distal end 304, through which vacuum is applied to theclear space created superiorly of plate 288. Vacuum tube 298 may bestraight and located in the center of plate 288 as shown, oralternatively may have a variety of other configurations and locationson the oral device as described elsewhere herein. Vacuum tube 298 mayterminate at a point anterior to apex A as illustrated, or may extend toa point further posterior on the plate 288. As an alternative to thevacuum tube 298 illustrated, a vacuum lumen may be formed integrallywithin plate 288 with outlet ports in the superior surface and/orinferior surface of plate 288 in communication with the vacuum lumen.

Oral device 280 further includes a lip seal 306 configured to be placedbetween the teeth and lips to help inhibit air from leaking between thelips so as to maintain a seal in the oral cavity. Lip seal 306 maycomprise a flexible polymeric sheet slidably mounted over extension tube300 and fluidly sealed therewith. Lip seal 306 will have sufficientflexibility to conform to the shape of the user's teeth and lips so asto provide a substantially air-tight seal.

Referring to FIG. 12E, tongue constraint 282 preferably engages andconstrains a region of the tongue T which is at least in part posteriorto the midpoint MP between the anterior end AE and the posterior end PEof hard palate HP. In the embodiment shown, tongue constraint 282extends in the posterior direction substantially the entire distancefrom the anterior end AE to the posterior end PE of hard palate HP, thusengaging both a medial region MR of the tongue T (roughly the middlethird) as well as regions of the tongue anterior and posterior to themedial region MR Tongue constraint 282 creates a posterior opening 0bounded superiorly by the hard palate, laterally by the teeth and bitestructure 284, and inferiorly by the posterior edge of plate 288. Thisposterior opening faces directly toward the soft palate SP and airway A,creating a vacuum flow path from the clear region CR directly to thesoft palate. This allows vacuum to be applied to at least the upperportion of the soft palate SP, from the superior end E1 where it joinsthe hard palate to a point closer the free inferior tip E2. Exertingvacuum force on the superior portion of the soft palate effectivelymaintains the entire soft palate structure in a position in which theairway is unobstructed.

In use, vacuum applied through vacuum tube 298 is directed to the tongueT through vacuum ports 296 and holds the tongue in engagement with theinferior surface of plate 288. Although some or all of vacuum ports 296may be blocked by the tongue, because the clear region maintained overoral device 280 is open posteriorly all the way to the soft palate, avacuum flow path is maintained from vacuum tube 298 directly to the softpalate. Thus the negative pressure within the clear region exerts aforce directly upon the soft palate through this vacuum flow path,maintaining the soft palate in an anterior position in which it does notobstruct the airway. Preferably, the suction force exerted on the softpalate through the clear region maintains the soft palate in sealingengagement with the tongue and/or with the soft palate landing pad 290,while the tongue is held in engagement with the inferior surface of thetongue restraint 282. This allows the airway to be substantially fluidlyisolated from clear space CR where the vacuum is applied such that thepressure gradient between the airway and the oral cavity increases, thusurging the soft palate, tongue and other posterior oral tissuesanteriorly out of the airway.

Still another embodiment of an oral device according to the invention isillustrated in FIGS. 13A-E. In this embodiment, oral device 310 isidentical to oral device 280 of FIGS. 12A-D except as described below.Oral device 310 has a bite structure 311 like that of the previousembodiment, and a tongue constraint 312 comprising a plate 313 with asoft palate landing pad 314. Unlike the straight posterior edge oflanding pad 290 in the previous embodiment, landing pad 314 has aposterior edge 315 with an arcuate shape that curves outwardly in theposterior and (optionally) inferior directions beyond the open end ofbite structure 311. With this shape landing pad 314 may be more suitablylocated to engage the soft palate in some patients. In addition, landingpad 314 optionally includes a plurality of ribs 318 extending laterallyacross landing pad 314. Ribs 318 stand in relief on the posteriorsurface 316 of landing pad 314 to enhance engagement with the softpalate tissue, as well as help to channel the vacuum flow laterally.Ribs 318 may comprise tubular, round, or partially-round strips affixedto landing pad 314, or ribs 318 may be integrally formed with landingpad 314. Ribs may also be provided along the superior surface of plate313 oriented either laterally like ribs 318 illustrated, in theanterior-posterior direction, or in other orientations.

A further difference from the embodiment of FIGS. 12A-D is the vacuumtube 320, which extends past apex A to a point near the posterior edge315 of oral device 310. In this way, vacuum tube 320 ensures thatnegative pressure is applied along the posterior edge of oral device310, a location closer to the soft palate. Vacuum tube 320 includes sideholes 322 and an open distal end 324 through which negative pressure maybe applied. Additionally, in this embodiment, tongue constraint 312 hasno vacuum ports extending through plate 313 as in the earlierembodiment.

Another unique aspect of oral device 310 is the placement of spacingelements 324 on the inferior surface 326 of bite structure 311. Spacingelements 324 are a soft pliable material, e.g. polymeric tubing or foam,having a thickness of about 2-12 mm. Each spacing elements 324 ispositioned at or near a posterior end 329 of bite structure 311 andextends anteriorly approximately 25-75% of the way around to the frontof bite structure 311. Alternatively, multiple spacing elements ofshorter length may be placed at intervals along each side of bitestructure 31. In this way spacing elements 325 sit between the patient'supper and lower teeth and hold open the lower jaw slightly. Such slightopening of the jaw during sleep has been shown to improve airway patencyin some circumstances.

A further unique aspect of oral device 310 is that a jaw positioning tab328 is disposed on the anterior closed end of bite structure 311 andextends downwardly therefrom sufficiently to engage the posteriorsurface of the lower front teeth when oral device 310 is positioned inthe oral cavity. Jaw positioning tab 328 is of sufficient stiffness andpositioned in a suitable location on bite structure 311 to maintain thepatient's lower jaw in a position slightly forward of a normal relaxedposition. Such forward positioning of the jaw has been found to improveairway patency in some circumstances.

It should be understood that ribs 318, spacing element 324, and jawpositioning tab 328 are optional features of oral device 310 and thatany or both of these features may be eliminated without departing fromthe scope of the invention or limiting its utility.

In other respects oral device 310 is similar to oral device 280 of FIGS.12A-D and operates in the same way. It will be understood that oraldevice 310 will usually include a lip seal like lip seal 306 of thepreviously described embodiment although in FIGS. 13A-D the lip seal isremoved for added clarity. It should be further understood that any orall of the features of oral device 310 may optionally be included inoral device 280 or in other embodiments described herein.

FIGS. 14A-C illustrate an oral device 330 identical to oral device 280of FIGS. 12A-D except an alternative configuration of vacuum tube 320 isshown. In this embodiment, vacuum tube 332 has a loop 334 extendingaround tongue constraint 313 near the outer edges thereof adjacent bitestructure 336 and along the posterior edge 338 of tongue constraint 313.Vacuum tube 320 has a plurality of side holes 337 distributed evenlyaround loop 334. A plurality of vacuum ports 339 are disposed in acentral region of tongue constraint 313 with loop 334 encircling most ifnot all of vacuum ports 339. In this way negative pressure isdistributed by vacuum tube 320 directly to the outer edges and posteriorregion of tongue constraint 313 to ensure adequate negative pressure isavailable in those regions. In addition, loop 334 more evenlydistributes negative pressure across a larger portion of the surface oftongue constraint 313.

FIGS. 15A-D illustrate an oral device 340 according to the inventionsimilar in many respects to oral device 280 of FIGS. 14A-D except, inplace of vacuum tube 320, oral device 340 has tongue constraint 341having a hollow interior chamber 342 enclosed between a superior wall344 and an inferior wall 346. A vacuum tube 348 is in fluidcommunication with chamber 342 and extends through inferior wall 346 andanteriorly through bite structure 350 where it may be connected to avacuum source. A plurality of inferior vacuum ports 352 extend throughinferior wall 346 in communication with chamber 342 and are positionedso as to apply suction to the tongue. A plurality of posterior vacuumports 354 extend through superior wall 344 in communication with chamber342 and are oriented to face in a posterior direction away from thetongue and toward the soft palate. Preferably, at least some ofposterior ports 354 are disposed in a plane P which is at an angle β ofat least about 45°, more preferably about 60°-180°, and most preferablyabout 90°-180° in the superior direction relative to the occlusal plane0 which contains the inferior surface 349 of bite structure 343.Optionally, posterior vacuum ports 354 may be further distributed alongthe upper portion of superior wall 344 so as to face the hard palate. Inthis way, vacuum may be conveyed through vacuum tube 348 into chamber342, from which suction is applied to the tongue through inferior vacuumports 352 and to the soft palate through posterior vacuum ports 354.

In the embodiment of FIGS. 15A-D, tongue constraint 341 has an overallthickness (or height) greater than that of oral device 280 in order toprovide room for chamber 342; however, superior wall 344 will preferablybe configured so that a clear region is maintained above tongueconstraint 341 between the top surface of superior wall 344 and the hardpalate when oral device 340 is positioned in the oral cavity. As analternative, FIGS. 16A-C illustrate an oral device 340A substantiallyidentical to oral device 340 except in this embodiment, the superiorwall 344A extends upwardly to the hard palate such that the clear regionCR formed by tongue constraint 341A is enclosed within chamber 342A. Inthis embodiment, superior wall 344A is shaped so as to conform generallyto the shape of the hard palate and there will be little or no spacebetween superior wall 344A and the surface of the hard palate when oraldevice 340A is positioned in the oral cavity. Posterior ports 354A aswell as inferior ports 352A are thus in direct communication with theclear region CR within chamber 342A. As in the embodiment of FIGS.15A-D, posterior ports 354A face away from the tongue and toward thehard palate, preferably lying in a plane which forms an angle of atleast about 45°, more preferably about 60°-180°, and most preferablyabout 90°-180° in the superior direction relative to the occlusal plane.

In the embodiment of FIGS. 17A-D, oral device 360 is similar to oraldevice 340 of FIGS. 15A-D, except that tongue constraint 362 comprisestwo separate hollow chambers within it, including an anterior chamber364 and a posterior chamber 366, each enclosed by a superior wall 368and an inferior wall 370. Preferably, tongue constraint 362 is a moldedconstruction with anterior chamber 364 and posterior chamber 366integrally formed within it. A transverse wall 372 divides anteriorchamber 364 from posterior chamber 366. A plurality of inferior ports374 are disposed in inferior wall 370 in communication with anteriorchamber 364, and a plurality of posterior ports 376 are disposed insuperior wall 368 in communication with posterior chamber 366. As inother embodiments, inferior ports 374 are positioned so as to applysuction to the tongue, while posterior ports 376 are positioned so as toface away from the tongue and toward the soft palate in order to applysuction to the soft palate and not be blocked by the tongue when it isengaged by inferior wall 370. As described above in connection withFIGS. 15A-D, at least some of posterior ports 376 are disposed in aplane which is at an angle of at least about 45°, more preferably about60°-180°, and most preferably about 90°-180° in the superior directionrelative to the occlusal plane. An anterior supply conduit 380 extendsthrough tongue constraint 362 from anterior chamber 364 to the anteriorend of tongue constraint 362, while a posterior supply conduit 382extends from posterior chamber 366 to the anterior end of tongueconstraint 362. A first vacuum tube 384 connects to anterior supplyconduit 380 and a second vacuum tube 386 connects to posterior supplyconduit 382, each vacuum tube extending through bite structure 388 andbeing configured to connect to a vacuum source.

Oral device 360 is particularly advantageous in that the negativepressures within anterior chamber 364 and posterior chamber 366 can becontrolled independently of one another. As illustrated in FIG. 17E,vacuum tubes 384, 386 may be connected to separate pressure regulators385A, 385B, which are in turn fluidly connected to a single vacuum pump387. Pressure regulators 385 are adjustable using control knobs 389A,389B to set the level of negative pressure applied through each ofvacuum tubes 384, 386. In this way, the negative pressure in each ofanterior chamber 364 and posterior chamber 366 (not shown in FIG. 17E)can be independently controlled and optimized to keep the soft palateand tongue free of the airway. For example, different pressures could beapplied to different regions of the oral cavity (e.g. the tongue and thesoft palate) to achieve the desired displacement of different tissues.In addition, air under positive pressure can be delivered through eithervacuum tube 384 or vacuum tube 386 while air at a different pressure ornegative pressure is delivered through the other vacuum tube, forpurposes of removing saliva from the vacuum tubes, delivering positivepressure to the airway or other regions, or achieving other desiredeffects. In an alternative embodiment, vacuum tubes 384, 386 may beconnected to two separate pumps which are independently controllable toadjust the level of positive or negative pressure delivered, as shown inFIG. 21C, described below.

Turning to FIGS. 18A-C, in a further embodiment, oral device 390 isconstructed identically to oral device 280 of FIGS. 12A-D except thattongue constraint 392 includes an inferior pad 394 adhered to theinferior surface of tongue constraint 392, and a posterior pad 396adhered to a posterior surface of tongue constraint 392. Inferior pad394 and posterior pad 396 are composed of a soft, flexible and porousmaterial such as Dacron, cotton, or foam, and are adapted to reducefriction and abrasion of the tongue and/or soft palate tissues whichengage tongue constraint 392. Inferior pad 394 and posterior pad 394 aresufficiently porous to allow vacuum to be applied through them frominferior vacuum ports 398 or posterior vacuum ports 399. It should beappreciated that either inferior pad 394 or posterior pad 396 mayoptionally be used without the other, and that either or both inferiorpad 394 or posterior pad 396 could be used with any of the otherembodiments described above or below.

FIGS. 19A-B illustrate a further embodiment of an oral device accordingto the invention. In this embodiment, like other embodiments elsewheredescribed, oral device 400 comprises a tongue constraint 402 and a bitestructure 404. Tongue constraint 402 comprises a dome-shape plate 403with a plurality of inferior vacuum ports 408 extending through plate403 in a central region thereof. An anterior vacuum tube 406 is fixed tothe superior surface of plate 403 and has a plurality of side holes 405through which vacuum may be conveyed.

Different from previously describe embodiments, a landing pad 410 ispivotally coupled to tongue constraint 402 by a transverse pin 412, sothat landing pad 410 is rotationally movable relative to plate 403.Landing pad 410 has a hollow interior chamber 414 enclosed by aposterior wall 416 and an anterior wall 418. A plurality of posteriorports 420 are disposed in posterior wall 416 in communication withchamber 414. As in the embodiments of FIGS. 15-17, posterior ports 420are configured to face the soft palate and away from the tongue,preferably being disposed plane which is at an angle β of at least about45°, more preferably about 60° 180°, and most preferably about 90°-180°in the superior direction relative to the occlusal plane. Notably, theangle of posterior ports 420 relative to the occlusal plane may bevaried by pivoting landing pad 410 relative to plate 403.

A posterior vacuum tube 422 is connected to anterior wall 418 incommunication with chamber 414. Posterior vacuum tube 422 extendsanteriorly along the inferior side of plate 403, which optionally mayinclude eyelets 424 through which posterior vacuum tube is slidablypositioned to keep it close to plate 403. Posterior vacuum tube 422extends slidably through bite structure 404 and a clamp 426 fixed to theanterior side thereof. Clamp 426 has a cap 428 threaded onto a taperedreceptacle 430 each having a central passage through which posteriorvacuum tube extends. Tapered receptacle 430 may be axially split and/orsufficiently conformable that tapered receptacle 430 is urged radiallyinward to engage posterior vacuum tube 422 as cap 428 is rotationallytightened. Of course, various clamps suitable for clamping posteriorvacuum tube 422 are well known and may be used in place of the exemplaryclamp illustrated. By sliding posterior vacuum tube 422 anteriorly orposteriorly, landing pad 410 is pivoted relative to plate 403. It shouldbe understood that pull wires, rods, or other means could be usedinstead of posterior vacuum tube to pivot landing pad 403.

Advantageously, different negative pressures may be applied throughanterior vacuum tube 406 and posterior vacuum tube 422 so that thesuction applied to the soft palate through posterior ports 420 may becontrolled independently of the suction applied to the tongue throughinferior ports 408. For example, oral device 400 may be used with thesystem illustrated in FIG. 19E or the system illustrated in FIG. 23C.When vacuum has been applied through posterior ports 420 such the softpalate has become engaged against landing pad 410, posterior vacuum tube422 maybe tensioned to pivot landing pad 410 anteriorly, thereby helpingto draw the soft palate further away from the patient's airway. Oncelanding pad 410 is in the desired position, clamp 426 may be tightenedto lock the posterior vacuum tube 422 and landing pad 410 in place.

Referring now to FIGS. 20 and 20A-B, in a further embodiment an oraldevice 434 comprises a tongue constraint 436 movably coupled to a bitestructure 438. Tongue constraint 436 has a superior wall 440 and aninferior wall 442 enclosing a hollow chamber 444. A plurality ofinferior ports 446 extend through inferior wall 442 in communicationwith chamber 444. A plurality of posterior ports 448 are disposed in aposterior region of superior wall 440 in communication with chamber 444.Posterior ports face toward the soft palate and away from the tongue toremain unobstructed by the tongue when vacuum is applied therethrough,preferably lying in a plane which is at an angle of at least about 45°,more preferably about 60°-180°, and most preferably about 90°-180° inthe superior direction relative to the occlusal plane. A vacuum tube 450is connected to tongue constraint 436 in communication with chamber 444and extends slidably through a channel 452 in bite structure 438. Aclamp 454 is mounted to bite structure 438 and is adapted to lock vacuumtube 450 in position relative to bite structure 438. Clamp 454 may beconstructed like clamp 426 of FIGS. 19A-B or may have any other knownclamp design suited for its purpose.

Bite structure 438 is U-shaped with a closed anterior end 439, an openposterior end 441, and an inner wall 456 along its interior side. A pairof channels 458 are disposed in inner wall 456 on opposing sides of bitestructure 438 near its open end 441. A pair of pins 460 are attached toopposing lateral sides of tongue constraint 436 and extend laterallythrough channels 458. Pins 460 are slidable in channels 458 so thattongue constraint 436 is movably anteriorly and posteriorly relative tobite structure 438. In this way, vacuum may be applied through vacuumtube 450 and chamber 444 so as to apply suction through inferior ports446 to the tongue, and through posterior ports 448 to the soft palate.When these tissues have been engaged, tension may be exerted on vacuumtube 450 to move tongue constraint 436 anteriorly relative to bitestructure 438, thereby retracting the tongue and soft palate furtherforward and away from the airway. Once in the desired position, vacuumtube 450 may be clamped in place by tightening clamp 454 so as to holdtongue restraint 436 in position relative to bite structure 438.

FIGS. 21A-B illustrate another embodiment of an oral device according tothe invention. In this embodiment, oral device 470 is identical to oraldevice 280 of FIGS. 12A-D except that oral device 470 is adapted todeliver air under positive pressure into the patient's airway while thetongue is constrained and negative pressure is applied to the softpalate and tongue. Oral device 470 includes at least one, preferably two(as shown), delivery conduits 472 fixed to the upper surface of tongueconstraint 474. Alternatively delivery conduits 472 may be fixed to bitestructure 476, e.g. to its inner wall 478 or to its inferior surface480. In the latter case delivery conduits 472 may serve the additionalpurpose of acting as a spacer between the patient's upper and lowerteeth to keep them slightly apart when the oral device is in place. As afurther alternative, all or part of delivery conduits 472 may be formedby an interior lumen (not shown) formed integrally within tongueconstraint 474 or bite structure 476. Delivery conduits 472 haveposterior portions 482 extending from the posterior edge 484 of tongueconstraint 474 with free posterior ends 486 adapted to extend into thepatient's airway. Delivery conduits 472 connect to a delivery tube 473which extends through bite structure 476 and is adapted to connect to afluid supply tube (not shown) outside the patient's oral cavity, whichin turn may be connected to pump (not shown) for delivering air or othergasses under positive pressure. Alternatively, delivery tube 473 may beopen to room air so that the airway is in communication with air outsidethe oral cavity in order to allow mouth breathing while the device is inplace and while the oral cavity seal is maintained.

As in the case of oral device 280, with oral device 470 in place in thepatient's oral cavity, tongue constraint 474 maintains at least aportion of the tongue in a position spaced apart from the patient's hardpalate so as to maintain a clear region superior to tongue constraint474. Negative pressure may be applied through vacuum lumen 488 to exertvacuum force on the soft palate and tongue, thereby causing the softpalate and tongue to be maintained in sealing engagement with oneanother anterior to the patient's airway, isolating the airway from theremainder of the oral cavity. The soft palate, tongue, and oral devicemay alternatively seal to each other in any combination in order tosubstantially fluidly isolate the airway. In this embodiment, deliveryconduits 472 are adapted to extend into the airway between the softpalate and tongue while still allowing these tissues to seal againsteach other and around the periphery of delivery conduits 472. Air orother suitable gasses may be delivered to the airway under positivepressure through delivery conduits 472 thereby enhancing the pressuregradient between the airway and the oral cavity, helping to urge thesoft palate and tongue anteriorly out of the airway and preferably insealing engagement with one another. Positive pressure delivered to theairway may also apply forces to other tissues in a manner that improvesairway patency.

A dual-pump system for use with oral device 470 is illustrated in FIG.21C. System 471 comprises a first pump 473 controlled via a control knob475A and a second pump 477 controlled via a second control know 475B. Afirst readout 479A displays the pressure level being applied by firstpump 473, while a second readout 479B displays the pressure level beingapplied by second pump 477. Delivery tube 473 is connected to first pump473 while vacuum tube 488 is connected to second pump 477. In this way,first pump 473 may deliver air under an adjustable level of positivepressure through delivery conduits 472, while second pump 477 may beadjusted to apply a desired level of negative pressure through vacuumlumen 488. Optionally, pressure lumens or sensors may be provided onoral device 470 to monitor negative pressure in the oral cavity and/orpositive pressure in the airway. These may be coupled to first andsecond pumps 473, 477 which may be automatically controlled to adjustpump speed or pressure to maintain desired pressure levels or a desiredpressure gradient between the airway and the oral cavity.

In a further embodiment of the invention, illustrated in FIGS. 22A-C, anoral device 580 is substantially identical to oral device 280 of FIGS.12A-D, except in this embodiment, oral device 580 comprises a tongueconstraint 581 having a plate 582 for engaging the patient's tongue anda landing pad 584 which extends in a generally superior direction from aposterior edge 586 of plate 582. As shown in FIG. 22C, landing pad 584has a posterior surface 588 at least a portion of which lies in a planeP which is at an angle a of at least about 30°, more preferably about45-135°, and most preferably about 60-100° relative to the occlusalplane H containing the inferior surface 589 of bite structure 590. Inthis way, posterior surface 588 is configured to receive and engage thesoft palate as it is drawn forward by vacuum pressure applied throughvacuum tube 592. Posterior surface 588 may have a curvature either orboth laterally right-left and superiorly-inferiorly so as to present aconcave surface into which the soft palate is drawn. The superior edge595 of landing pad 584 preferably has an arched shape corresponding tothe shape of the hard palate, and may be configured to engage the hardpalate and even to seal therewith, or alternatively may be spaced apartfrom the hard palate. In addition, posterior edge 586 of plate 582,which forms the inferior edge of landing pad 584, may be disposed invarious positions relative to the occlusal plane H, including bothsuperior and inferior to plane H. In a particular embodiment, posterioredge 586 is disposed a distance d of about 2-7 mm, more preferably about3-6 mm, inferior to plane H.

A plurality of posterior ports 596 are disposed in landing pad 584 andextend through its thickness so that, with oral device 580 in place inthe patient's oral cavity, posterior ports 596, lying in plane P, facein a posterior direction directly toward the soft palate. In this way,the clear region created superior to plate P and below the hard palatecommunicates directly with the soft palate through posterior ports 596so that vacuum applied through vacuum tube 592 is applied directly tothe soft palate via posterior ports 596. Moreover, the verticalorientation of landing pad 584 and posterior ports 596 therein allowsvacuum to be applied to the entire soft palate, from its free inferiortip to its posterior end where it attaches to the hard palate, enhancingthe effectiveness of displacing the soft palate from the patient'sairway. Because the patient's tongue is constrained under the inferiorsurface of plate 582, the tongue cannot be pulled by the vacuum forcesto obstruct posterior ports 596. Inferior ports (not shown) mayoptionally be provided in plate 582 through which vacuum may be exertedupon the superior surface of the tongue, similar to the embodiment ofFIGS. 12A-D.

Referring now to FIGS. 23A and 23B, a further exemplary oral device 610constructed in accordance with the principles of the present inventioncomprises a U-shaped base or anchor structure 612 having a lip seal 614at its forward or anterior end. A tongue-engaging member 616 is heldbetween the posterior ends of right and left legs of the U-shaped base612, and a vacuum tube 618 passes into the device and is open within aplenum 620 in order to draw a vacuum within the device. In particular,the plenum 620 is open to an interior 622 of the tongue-engaging member616 so that the vacuum may be drawn via a conduit 624 provided throughone of the connecting wings 626 which couple the tongue-engaging member616 to the base 612. A plurality of ports 628 are formed over aposterior surface 630 of the tongue-engaging member 616 so that a vacuummay be applied within the oral cavity when the device 610 is held withthe base anchor 612 positioned between the patient's upper and lowerteeth. Typically, the patient's teeth will be placed within upper andlower channels 613 (with only the upper channel being shown in FIGS. 23Aand 23B) which are formed in the upper or superior and lower or inferiorsurface of the base 612.

As best shown in FIG. 24, the tongue-engaging member 616 has both theposterior surface 630 and an anterior surface 632, where the anteriorsurface will engage the tongue when the base 612 is held between thepatient's teeth. The anterior surface of the tongue-engaging member willtypically be flat or slightly curved in order to engage a medial regionof the tongue over a relatively large surface area, typically in therange from 300 mm2 to 1000 mm2, usually from 550 mm2 to 750 mm2. Ofparticular interest to the present invention, the tongue-engaging member616 will be inclined with an upper end or lip 634 displaced in ananterior direction (toward the lip seal 614) and a lower or inferior lipor edge 636 being displaced in a posterior direction. Thetongue-engaging member 616 will typically have a center line 638 (shownin broken line) which is inclined at an angle a in the range from 30° to70°, usually from 45° to 60°, relative to a plane 640 (shown in brokenline) of the base, which is positioned between the patient's teethduring use of the device. The relatively large area of the anteriorsurface 632 of the device 610 combined with the angle of inclination,which is generally inclined forwardly relative to a plane of the basewhen the base is positioned between the upper and lower teeth, combinesfor particularly effective anterior displacement of the patient's tonguewhile creating a clear region above the medial region of the tongue inorder to apply a vacuum to close the soft palate against the posteriorregion of the tongue, as described in more detail below.

Oral device 650 (FIG. 25) represents a second embodiment of the presentinvention and includes a U-shaped base or anchor 652 having an enlargedlip seal 654 at its anterior end. A tongue-engaging member 656 iscarried at the posterior end of the base 652 and has a body which isgenerally aligned along a plane 658 (shown in broken line) which isdisposed at the same angle a relative to the plane of the base 660(broken line) as with the first device illustrated in FIG. 24. Aprincipal difference of the oral device 650 is that an upper edge 662 ofthe tongue-engaging member 656 is inclined in a forward or anteriordirection, generally with a curved anterior surface 664. The remainingaspects of the oral device 650 are generally the same as described abovewith respect to the first oral device 610. Use of the oral device 650 isdescribed in more detail in connection with FIGS. 28 and 29.

Referring now to FIG. 26, an oral device 670 comprises a U-shaped baseor anchor 672 having a lip seal 674 at its forward or anterior end. Avacuum tube or line 676 is connected to the device in order to apply avacuum within an interior of the base 672. A tongue-engaging member 678comprises a right half 80 and a left half 682 (where right and left areviewed from the anterior end of the device which includes the lip seal674). Each of the right and left halves 680 and 682 are connected to avacuum plenum (not illustrated) formed through both sides of theinterior of base or anchor 672 so that the vacuum applied through vacuumtube 676 is carried through to the ports 684 and 686 formed on the twohalves, respectively. The angle of inclination of the two halves willtypically be identical, but it could vary by a small amount withoutdeparting from the effectiveness of the present invention. Theinclination angle(s) and total contact area of the anterior surfaces ofthe halves 680 and 682 are also within the ranges set forth above, sothat the effectiveness of the device is generally the same as describedfor the previous devices.

Referring now to FIG. 27, an oral device 690 represents a fourthembodiment of the present invention and comprises an interior bite plateand lip seal 692 connected to a single axial bridge 694 which carries atongue-engaging member 696 at its posterior end. The tongue-engagingmember 696 has generally the same dimensions and is inclined at the sameangle relative to a bite plane as described with the prior embodiments.A vacuum is applied through a vacuum tube 698 which is connected via aplenum (not shown) within the single axial member 694 which opens to theinterior of the tongue-engaging member 696. The vacuum is appliedthrough a plurality of ports 700. The device 690 is less bulky than theprior embodiments.

Referring to FIGS. 28 and 29, use of the device 650 for positioningtongue-engaging member 656 against a tongue within an oral cavity willbe described. In a first instance, as shown in FIG. 28, anterior surface657 of the tongue-engaging member 656 engages the medial region of thetongue T to push or displace the tongue in an anterior direction. Byapplying a vacuum through ports on the posterior surface 659, the softpalate SP is also drawn in an anterior direction so that a posteriorportion PP of the palate seals against a posterior region PR of thetongue, as illustrated. The region of the soft palate above theposterior portion is also drawn against the posterior surface 659 of thetongue-engaging member 656, to further stabilize the soft palate totreat the breathing disorder.

The portion of the soft palate SP above the posterior portion PP neednot be engaged against the posterior surface 659 of the tongue-engagingmember 656. As shown in FIG. 29, an open space OS may remain between theposterior surface 659 and the soft palate SP while the posterior portionPP of the soft palate remains engaged with the posterior region PR ofthe tongue. The soft palate remains sufficiently stabilized in order totreat the breathing disorders within the methods of the presentinvention.

While the above is a complete description of the preferred embodimentsof the invention, various alternatives, modifications, substitutions,and equivalents may be used. Therefore, the above description should notbe taken as limiting the scope of the invention, which is defined by theappended claims.

What is claimed is:
 1. A method for improving airway patency in a patient having an oral cavity, a hard palate, a soft palate, a tongue, and an airway, said method comprising: positioning an oral device in the oral cavity; applying a negative pressure from the device into posterior regions of the oral cavity while at least a first leg of said device is positioned along a side of the tongue, wherein the negative pressure is applied through the leg and causes the soft palate and tongue to form a seal whereby the patient's airway is fluidly isolated from the oral cavity anterior to the seal.
 2. A method as in claim 1, further comprising delivering air to the oral cavity.
 3. A method as in claim 2, wherein applying delivering air to the oral cavity comprises: applying a positive pressure from the device into posterior regions of the oral cavity along a side of the tongue.
 4. A method as in claim 3, wherein the positive pressure is applied from a positive pressure lumen adjacent to the lumen applying the negative pressure the one side of the oral device.
 5. A method as in claim 4, wherein the positive pressure is applied through a pair of positive pressure lumens, one on each side of the tongue.
 6. A method as in claim 5, wherein the positive pressure is applied through a pair of positive pressure lumens which are adjacent to a pair of negative pressure lumens, one on each side of the tongue.
 7. A method as in claim 1, wherein the negative pressure is applied from a lumen in the at least first leg on one side of the oral device.
 8. A method as in claim 7, wherein the lumen is integral with or coupled to the oral device.
 9. A method as in claim 7, wherein the vacuum is applied through ports on the lumen oriented toward the tongue.
 10. A method as in claim 1, wherein the negative pressure is applied laterally from the device into posterior regions of the oral cavity along both sides of the tongue.
 11. A method as in claim 10, wherein the negative pressure is applied through a pair of lumens, one on each side of the tongue.
 12. A method as in claim 1, further comprising sealing the patient's lips to inhibit air entering the oral cavity while the vacuum is being applied.
 13. A method as in claim 12, wherein sealing the patient's lips comprises positioning a sealing structure between the patient's lips and the patient's teeth.
 14. A method as in claim 1, wherein the negative pressure in a range from −5 cm H₂O to −150 cm H₂O.
 15. A method as in claim 1, further comprising repositioning the patient's jaw from an undeflected position to a deflected position, and maintaining the jaw in the deflected position while the vacuum is applied.
 16. A method as in claim 1, further comprising collecting saliva aspirated from the oral cavity by the vacuum. 